Aralkyl polyhydric phenol



Patented July 1, 1941 UNITED STATES PATENT OFFICE'T 2.247.404 ARALKYLronmrnmc rnENoL Ralph P. Perkins and Fred Bryner, Midland,

Mich assignors to The Dow Chemical Company, Midland, Micln, acorporation of Michigan No Drawing. Application March 24, 1939, SerialNo. 263,912

g 14 Claims. (01. 260-619) This invention relates to a class of newaralkyl polyhydric phenols and to a method of makin the same.

The new compounds of the invention correspond to the general formulawherein X is a polyhydroxy aryl or halo-aryl radical of the benzeneseries, and R is hydrogen or a lower alkyl radical. They are useful asgermicides and fungicides, -as intermediates in the manufacture ofsynthetic resins and insecticides, as polymerization inhibitors, and insome cases as photographic developing agents,

. Our new products may be prepared by reacting a 2-phenyl-1-allrene, e,g. styrene, alphamethyl styrene, alpha-ethyl styrene, etc., with asuitable phenol, i. e. with a polyhydroxy benzene or halo-benzenecontaining not more than live i added slowly with agitation. When suchaddition is complete, themixture is maintained at the operatingtemperature for a time to allow completion of the reaction: the catalystis removed or destroyed by suitable known means, and the mixture isfractionally distilled at reduced pressure to separate the desiredaralkyl polyhydric phenol. If the phenol to be condensed is a solid atoperating temperatures, the reaction may be Under .these, conditions,the product of reaction consists chiefly of a para-substituted aralkylphenol, unless the phenolic reactant has no position para to a hydroxylgroup open for substitution, in which case the aralkyl'group enters theortho position.

The following examples illustrate the invention, but are not to beconstrued as limiting its scope:

Example 1 A mixture of 2 mols (220 grams) of catechol and 1 c. c. ofconcentrated hydrochloric acid was heated to a temperature of 120 C.,and 1 mol (118 grams) of alpha-methyl styrene was added with agitationduring 0.6 hour. The resulting mixture was then heated at l20 -150 C.for 0.5 hour to insure completion of the reaction. The crude product wasthen cooled, neutralized with aqueous sodium hydroxide, and fractionallydistilled at an absolute pressure of 7 millimeters of mercury. In thisway there were recovered some unreacted alpha-methyl styrene andcatechol, and 185.7 grams of 4-(alpha phenyl isopropyl) catechol a whitecrystalline solid having a freezing point of 94.5 C. After repeatedrecrystallization from cyclohexane, the product had a freezing point ofcarried out in an inert solvent. The reactants may be mixed in anydesired proportions, but

in most instances we prefer to use 1.5 to 2.5 mols of polyhydric phenolper mol of styrene compound.

In practice we may employ acid-activated bleaching earths, and the like.For most reactions, however, it is preferable to use hydrogen chlorideor hydrogen bromide, either per se or in aqueous solution, as catalyst.

- any of the usual.

condensation catalysts, e'. g. aluminum chloride, ferric chloride,sulfuric acid, phosphoric acid,

97 C., and a boiling point of 216 C. at 10 millimeters pressure. Athigher pressures the compound decomposes on boiling. The yield was 84per cent, basedon the catechol consumed.

Example 2 Resorcinol was reacted with alpha-methyl styrene and the crudeproduct was then purl- ,fied, according to the procedure in Example 1.

There was obtained 4-(alpha phenyl isopropyl) resorcinol OH OH: Icourt-G011 a white crystalline solid having a melting point of 126 0.,and a boiling poin" of 210 C, at 10 millimeters pressure. V I

7 Example 3 A mixture of .2 mols (220 grams) of hydroquinone and 30. e.of concentrated hydrochloric 4 acid was dissolved in glacial aceticacid, and was heated to a temperature oi about 140 (3. 1 mol (118-grams) of alpha-methyl styrene was then added with agitation during 0.5hour, after which the mixture was heated for 2.5 hours moreto completethe reaction. The resulting crudematerial was cooled and fractionallydistilledat reduced pressure to remove the acetic acid solvent and toseparate the reaction products. There was obtained Z-(alpha phenyiisopropyl) hydroquinone 0H CH3 Cufira white crystalline solid having amelting point of 111C. and a boiling point of 219 C. at 10 millimeterspressure.

Other modes of applying the principle of the invention may be employedinstead of those explained, change being made as regards the detailsdisclosed, provided the product or method stated 'in any of thefollowing claims or the equivalent of such stated product or method beobtained or employed.

We claim:

1. An aralkyl polyhydric phenol corresponding to the general formulaCoHr-I wherein X is a polyhydroxy aryl radical of the benzene series,and R is a lower alkyl radical. v An (alpha phenyl isopropyl) dihydroxybenzene.

4. 4-(alpha phenyl isopropyll catechol.

5. 4-(alpha phenyl isopropyl) resorcinol.

6. 2-(alpha phenyl isopropyll hydroauinone.

7. The method of preparing an arallsyi poly hydric phenol whichcomprises reacting a 2-phenyI-Lalkene selected from the class consistingof alpha methyl styrene and alpha ethyl styrene with a phenolic compoundselected from the class consisting of polyhydroxy aromatic hydrocarbonsand polyhydroxy aromatic halo-hydrocarbons oi the benzene series, in thepresence of a condom sation catalyst.

aerator 8. The method of preparing an aralkyl polyhydric phenol whichcomprises reacting a 2- phenyl-l-alkene selected from the class consist=ing of alpha methyl styrene and alpha ethyl styrene with a phenoliccompound selected from the class consisting ofspolyhydroxy aromatichydrocarhongand polyhydroxy aronratichalo-hydrocarbons of the benzeneseries, in the presence of a small proportion of a condensationcatalyst.

9. The method of preparing an aralkyl polyhydric phenol which comprisesreacting a 2- phenyl-l-alkene with a phenolic compound selected from theclass consisting of polyhydroxy aromatic hydrocarbons and polyhydroxyaromatic halo-hydrocarbons of the :benzene series. in the presence of asmall proportion of a hydrogen halide selected from the class consistingof hydrogen chlorideand hydrogen bromide.

10. The method of preparing an aralkyl polyhydric phenol which comprisesreacting a 2 phenyl-l-alkene with a polyhydroxy aromatic hydrocarbon ofthe benzene series in the presence of a small proportion of a hydrogenhalide selected from the class consisting of hydrogen chloride andhydrogen bromide.

11. The method of preparing an (alpha-phenyl isopropyl) dihydrlc phenolwhich comprises reacting alpha-methyl styrene with a dihydroxy benzenein the presence of a small proportion of a condensation'catalyst.

12. The method of preparing an (alpha-phony! isopropyl, dihydric phenolwhich comprises reacting alpha-methyl styrene with a dihydroxy benzenein the presence of a small proportion of a hydrogen halide selectedfromthe class consist ing of hydrogen chlorideand hydrogen bromide' 13.The method of preparing an aralkyi polyhydric phenol which comprisesreacting a 2- phenyl-l-alkene with a phenolic compound selected from theclass consisting of polyhydroxy aromatic hydrocarbons and poiyhydroxyaro-v

